Japanese Patent Application Publication No. H 10-141954 discloses an obstacle detection apparatus for detecting an obstacle on a planned travel route of a moving body. The obstacle detection apparatus disclosed in Japanese Patent Application Publication No. H 10-141954 extracts a part corresponding to a travelling road surface from a three-dimensional image based on three-dimensional coordinate positional data on a travelling road and a current three-dimensional position of the moving body and detects an obstacle from the extracted part corresponding to the travelling road surface.
The above-mentioned conventional obstacle detection apparatus, however, suffers from a problem of: detecting only an obstacle existing on the surface of a planned travel route of the host vehicle; being thus incapable of detecting an object currently not existing on the surface of the planned travel route of the host vehicle; and being accordingly incapable of beforehand detecting an object which is likely to cross the host vehicle in the future.